Lampholder

ABSTRACT

A lampholder for connecting a fluorescent lamp to a supply circuit and for connecting a ballast or other starting circuit for the fluorescent lamp to the supply circuit. The lampholder includes a housing defining an opening for insertion of a lamp connection pin and a contact accommodating recess communicating with the opening. First and second elongated contacts are mounted in the recess in overlying relationship and are held in spaced apart relationship. The first contact includes a planar contact making section which makes a pin seat section of the second contact so the first contact engages the connection pin whenever the second contact engages the connection pin.

United States Patent Francis [451 Mar. .21, 1972 [72] inventor:

[52] US. Cl. ..339/53, 339/95 D Primary Examiner-Marvin A. Champion Assistant Examiner-Terrell P. Lewis Attorney-John M. Stoudt, Radford M. Reams, Ralph E. Krisher, Jr., Frank L. Neuhauser and Oscar B. Waddell [5 7] ABSTRACT A lampholder for connecting a fluorescent lamp to a supply circuit and for connecting a ballast or other starting circuit for the fluorescent lamp to the supply circuit. The lampholder includes a housing defining an opening for insertion of a lamp connection pin and a contact accommodating recess communicating with the opening. First and second elongated contacts are mounted in the recess in overlying relationship and are held in spaced apart relationship. The first contact includes a planar contact making section which makes a pin seat section of the second contact so the first contact engages the connection pin whenever the second contact engages the connection pm.

5 Claims, 6 Drawing Figures LAMPHOLDER BACKGROUND OF THE INVENTION The present invention relates to lampholders for fluorescent lamps and more particularly to such lampholders for connecting both a lamp and its related ballast to a supply of electric energy.

With many fluorescent lamps, particularly those referred to as "instant start" or rapid start," it is desirable to have the filament of the lamp connected in the supply circuit at all times when the ballast associated with that lamp is connected in the supply circuit. In prior art lampholders for such lamps at least one of the lamp connection pins deflects a line contact and brings it into engagement with a ballast contact.

Fluorescent lamp connection pins and lampholder contacts often have oxidation of their surfaces, which can prevent good electrical contact therebetween. Many prior art lampholders utilize contacts which are constructed and disposed such that an inserted lamp connection pin engages a relatively thin edge of the contact for improving the resulting electrical connection. Such contacts are often referred to as edge wipe contacts. U.S. Pat. No. 3,337,837 issued to John M. Pistey on Aug. 22, 1967, and assigned to General Electric Company, assignee of the present invention, shows and describes a very advantageous contact of this general type. Engagement of the lamp connection pin with the edge of that type of contact causes the contact to move relative to the pin with a twisting or torsion action, assuring good electrical connection.

There has not been in the prior art any lampholders which successfully provided a concurrent connection contact arrangement desirable for instant start and rapid start lamps using an edge wipe contact for insuring good electrical contact.

SUMMARY OF THE INVENTION Accordingly it is an object of the present invention to provide an improved lampholder for fluorescent lamps.

Another object is to provide such animproved lampholder which assures an associated lamp is connected in the electric supply circuit whenever its ballast is connected in the circuit.

A further object of this invention is to provide such an improved lampholder in which the line contact is of the edge wipe" type.

In carrying out the invention, in one form thereof, there is provided a lampholder including an opening for insertion of a connection pin of a lamp and further defining a contact accommodating recess. First and second elongated contacts are mounted in the recess and disposed for engagement by the connection pin. The contacts overlie one another for at least part of their length and the housing includes means retaining them in spaced apart relationship.

BRIEF DESCRIPTION OF THE DRAWING The subject matter which I regard as my invention is particularly pointed out and distinctly claimed in the concluding portion of the specification. The invention itself, however, together with further objects and advantages thereof, may be best understood by reference to the following description taken in conjunction with the accompanying drawing in which:

FIG. 1 is a side elevational view of a lampholder incorporating one embodiment of the present invention and illustrating a tubular fluorescent lamp mounted in the lampholder;

FIG. 2 is a front elevational view of the lampholder of FIG.

FIG. 3 is a rear elevational view of the lampholder of FIG. 1 but with the cover removed for purposes of illustration;

FIG. 4 is a cross-sectional view generally as seen along line 4-4 in FIG. 3, with some parts broken away and with the cover in place for purposes of illustration;

FIG. 5 is a cross-sectional view generally as seen along line 5-5 in FIG. 3, with the cover in place; and

FIG. 6 is a perspective view of one contact used in the lampholder ofFIGS. 1-5.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawing there is shown a lampholder 10 incorporating one embodiment of the present invention. The exempliflcation lampholder 10 is of the general type for use with tubular fluorescent lamps of the bi-pin type such as that partially shown at 11. Such lamps include a pair of spaced apart connection pins 12, 13. The lampholder 10 is formed with a molded base 14, formed from some suitable material such as a phenolic resin and having a front 15 and an open back 16. The lampholder also includes a removable cover 17 which is mounted over the open back 16 of the base by some suitable means such as a staple 18 to complete an essentially closed housing to receive suitable contacts.

Viewing particularly FIG. 2, it will be seen that the front 15 is provided with an opening 19 to receive the spaced apart connection pins 12, 13 of a lamp. As is well-known in the art, for mounting the lamp in the lampholder the lamp is rotated so that the connection pins 12, 13 enter the opening 19 through a gap 20 with one of the pins passing beyond a pair of separated lugs 217 Then the lamp is rotated degrees so that the connection pins are then positioned one to the outside of each of the lugs 21 (as seen in FIG. 2).

Viewing now particularly FIG. 3 it will be seen that the housing, particularly the molded base 14, defines a pair of elongated contact receiving recesses 22, 23 to receive associated elongated contacts and that each of the recesses 22, 23 communicates with the opening 19. Thus the connection pins 12, 13, when completely inserted in the opening 19, also extend-into the elongated recesses 22, 23 respectively. The recess 22 has appropriate ridges such as those shown at 24, 25 and 26 to laterally position an elongated contact 27. The contact 27, for instance, may be generally of the torsion contact type of edge wipe contact shown and described in the U.S. Pat. No. 3,337,837. The contact 27 includes a return bent portion 28 which fits closely around a generally transverse partition 29 so that, when the cover 17 is mounted to the base 14, the contact 27 will be securely positioned within the recess 22.

The recess 23 is formed somewhat differently than the recess 22. The molded base 14 includes a divider 30 extending generally longitudinally into the recess 23 at the end opposite the opening 19 for dividing that end portion of the recess 23 into a pair of spaced apart recess sections 31 and 32. A transverse partition 33 extends across the recess section 31. A platform 34 is formed between the transverse partition 33 and the opening 19 and is spaced somewhat from the inside of the front wall 15 of the lampholder. Extending beyond the platform 34 away from the front wall 15 are a lug 35 and a separator or separation wall 36. A pair of ridges of lugs 37 are formed in the recess section 31 and an additional lug or ridge 38 is formed in the main part of recess 23 between the platform 34 and the opening 19.

A pair of elongated contacts 39 and 40 are received in the elongated recess 23 in a generally overlying relationship for at least part of their lengths. The contact 39 is basically similar to the contact 27 and is of a thin blade construction. It has a planar contact making section 41 which is adjacent the inside surface of front wall 15 and overlies the opening 19 in the front wall 15. Contact 39 also includes a return bent or U- shaped mounting section 42 which is laterally offset from the contact making section 41 and fits closely about the transverse partition 33. The contact making section 41 and the mounting section 42 are connected by a somewhat twisted torsion section 43 so that while contact making section 41 is generally planar and is adjacent front wall 15 it is normally canted somewhat with respect to the wall 15. The other end of contact 39, that is the end on the other side of the mounting section 42 from the contact making section 41, is formed as a terminal section 44 which has a generally V-shaped groove 45 to bear against a conductor inserted into the housing through an opening 46 (shown in FIG. 2).

Contact 40 includes a pin seat section 47 which is slightly V- shaped to form a pin seat 48. The contact 40 is provided with an offset 49 which connects the pin seat section 47 to a mounting section 50. The mounting section 50 is formed as a generally right angle bend so that its end remote from pin seat section 47 fonns a short leg 51. The end of the short leg 51 is joined to a terminal section 52 through another generally right angle bend.

When the contact 40 is mounted in the housing, the mounting section 50 is supported on a platform 34 and nestled between the lug 35, separator 36 and middle wall 53 of base 14. The short leg 50 extends between the lug 35 and the separator or separation wall 36 and generally transversely across the recess 23. This positions the contact 40 so that the pin seat section 47 overlies the contact making section 41 of contact 39 at least in the area of opening 19 while the spacing of the platform 34 relative to the inside surface of front wall maintains the pin seat section 47 and the short leg 50 spaced from the contact 39. The terminal section 52 is received in the recess section 32 and is prevented from contacting terminal section 44 of contact 39 by the divider 30. A suitable wire or lead 55 is connected to terminal section 52 by some suitable means such as solder 56. The lead 55 extends from the housing through an opening 57 (see FIG. 4).

The separator 36 precludes any accidental contact between the mounting section 50 of contact 40 and the mounting section 42 of contact 39. When the cover 17 is placed over the open back of the base 14, it bears against or closely overlies the mounting section 50 and terminal section 52 of the contract 40 and the return bent mounting section 42 of the contact 39 so as to complete the mounting of the two contacts 39 and 40 within the housing such as they are maintained in the spaced apart relationship.

With this arrangement the contact making section 41 of the contact 39 masks the pin seat section 47 of the contact 40 from the front of opening 19. Thus when the connection pins of a suitable device, such as a bi-pin fluorescent lamp, are inserted into the opening 19, the connection pin 13 must first engage and move contact making section 41 before it will engage the pin seat section 47. The pin seat section 47 is constructed such that when the fluorescent lamp is fully mounted the connection pin 13 will rest in the pin seat 48.

Assume the fluorescent lamp 11 to be of the rapid start or instant start type, for instance, wherein the associated ballast is to be connected to the line only when the fluorescent lamp is installed and thus connected to the electrical supply. The contact 40 would be connected to one of the supply leads through conductor 55 connected to the terminal portion 52 of contact 40. The ballast lead would be connected to contact 39 through an appropriate wire inserted through opening 46 to engage terminal portion 44 at the V-shaped groove 45. Thus the ballast would be connected into the circuit through the contact 39, the connection pin 13 and contact 40 to the supply lead. Therefore, since connection pin 13 can engage the pin seat section 47 of contact 40 only when it has engaged and moved the edgewise contact 39, the ballast will be connected only when the lamp is connected in the circuit. The spacing of the platform 34 from the inside surface of front wall 15 is sufficient to allow this movement of the contact 39 without engaging contact 40 even when the contact 39 is an edgewise contact of the torsion type wherein the movement is a torsion or twisting action which will cause the contact making section 41 to occupy more space front to back in the lampholder.

It should be apparent to those skilled in the art that while I have described what at present is considered to be the preferred embodiment of this invention, in accordance with the Patent Statutes, changes may be made in the disclosed apparatus without actually departing from the true spirit and scope of this invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A lampholder including: a hollow base defining an opening in a first wall thereof for insertion of the connection pin of a lamp; said base further defining a contact accommodating recess; a first elongated contact received in said recess and including an edge wipe contact making section for engaging the lamp connection pin, a terminal sectron remote from said contact making section including means for releaseably engaging a conductor extending to the exterior of the lampholder, and a mounting section, said contact making section being disposed adjacent said first wall and exposed through the opening therein; a second contact received in said recessand having a pin seat section for engaging the lamp connection pin, a terminal section remote from said pin seat section, and a mounting section, said pin seat section normally overlying said contact making section of said first contact across the opening in said first wall and being positioned further from said first wall than said contact making section; a divider disposed between said terminal sections; and means fixedly securing said mounting sections of said contacts in said base with said contacts in spaced apart relationship so that a lamp connection pin inserted in the opening in said first wall will first engage said edge wipe contact making section and thereafter engage said pin seat section.

2. A lampholder including: a hollow base defining an opening in a first wall thereof for insertion of the connection pin of a lamp; said base further defining an elongated contact receiving recess communicating with said opening; said base having a generally transverse partition extending at least partially across said recess in spaced relationship with said opening; a first contact received in said recess; said first contact including an elongated planar contact making section positioned generally parallel to said first wall and overlying said opening; said first contact also including a return bent mounting section positioned closely around said generally transverse partition; said base also including a platform positioned farther from said first wall than said contact making section of said first contact; a second contact received in said recess; said second contact including an elongated pin seat section overlying said opening and a mounting section overlying said platform for spacing said pin seat section from said contact making section; said lampholder further including a cover closely overlying said mounting sections.

3. A lampholder as set forth in claim 2 wherein said contact making section masks said pin seat section so that an inserted connection pin engages said contact making section prior to engaging said pin seat section.

4. A lampholder as set forth in claim 2 wherein said first contact includes a terminal section on the side of its mounting section remote from said contact making section; said second contact includes a terminal section on the side of its mounting section remote from said pin seat section; and said base includes a divider positioned between said terminal sections.

5. A lampholder as set forth in claim 2 wherein said mounting section of said second contact includes a portion extending generally transverse of said contact receiving recess adjacent said mounting section of said first contact and said base includes a separator positioned therebetween. 

1. A lampholder including: a hollow base defining an opening in a first wall thereof for insertion of the connection pin of a lamp; said base further defining a contact accommodating recess; a first elongated contact received in said recess and including an edge wipe contact making section for engaging the lamp connection pin, a terminal section remote from said contact making section including means for releaseably engaging a conductor extending to the exterior of the lampholder, and a mounting section, said contact making section being disposed adjacent said first wall and exposed through the opening therein; a second contact received in said recess and having a pin seat section for engaging the lamp connection pin, a terminal section remote from said pin seat section, and a mounting section, said pin seat section normally overlying said contact making section of said first contact across the opening in said first wall and being positioned further from said first wall than said contact making section; a divider disposed between said terminal sections; and means fixedly securing said mounting sections of said contacts in said base with said contacts in spaced apart relationship so that a lamp connection pin inserted in the opening in said first wall will first engage said edge wipe contact making section and thereafter engage said pin seat section.
 2. A lampholder including: a hollow base defining an opening in a first wall thereof for insertion of the connection pin of a lamp; said base further defining an elongated contact receiving recess communicating with said opening; said base having a generally transverse partition extending at least partially across said recess in spaced relationship with said opening; a first contact received in said recess; said first contact including an elongated planar contact making section positioned generally parallel to said first wall and overlying said opening; said first contact also including a return bent mounting section positioned closely around said generally transverse partition; said base also including a platform positioned farther from said first wall than said contact making section of said first contact; a second contact received in said recess; said second contact including an elongated pin seat section overlying said opening and a mounting section overlying said platform for spacing said pin seat section from said contact making section; said lampholder further including a cover cloSely overlying said mounting sections.
 3. A lampholder as set forth in claim 2 wherein said contact making section masks said pin seat section so that an inserted connection pin engages said contact making section prior to engaging said pin seat section.
 4. A lampholder as set forth in claim 2 wherein said first contact includes a terminal section on the side of its mounting section remote from said contact making section; said second contact includes a terminal section on the side of its mounting section remote from said pin seat section; and said base includes a divider positioned between said terminal sections.
 5. A lampholder as set forth in claim 2 wherein said mounting section of said second contact includes a portion extending generally transverse of said contact receiving recess adjacent said mounting section of said first contact and said base includes a separator positioned therebetween. 